Automatic immersion apparatus



Dec. 5, 1967 H. J. DAVIS ET AL AUTOMATIC IMMERSION APPARATUS 5 Sheets-Sheet 1 Filed Dec. 22, 1965 INVENTORS HUGH J. DAVIS IRWIN S. LERNER M c4,

ATTORNEYS.

Dec. 5, 1967 J, DAVIS ET AL 3,356,096

AUTOMATI C IMMERS ION APPARATUS Filed Dec. 22, 1965 5 Sheets-Sheet 2 FIG. 4.

INVENTORSY HUGH J. DAVIS IRWIN s. LERN BY M 0Z1 wmw.

ATTORNEYS.

H. J. DAVIS ET AL Dec. 5, 1967 AUTOMATIC IMMERS ION APPARATUS 5 snets-Sheet 5 Filed Dec. 22, 1965 FIG. I

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United States Patent 3,356,096 AUTOMATIC IMMERSION APPARATUS Hugh J. Davis, Baltimore, Md, and Irwin S. Lerner, Greenwich, Conn., assignors to Lerner Laboratories, Inc., Greenwich, Conn., a corporation of Connecticut Filed Dec. 22, 1965, Ser. No. 515,663 19 Claims. (Cl. 134-58) This invention relates to automatic immersion apparatus and especially to automatic immersion apparatus for the treatment of histologic tissue preparatory to microscopic examination thereof.

Prior to the microscopic examination of tissue, it is necessary to put the tissue through a number of different treatments to condition it for examination.

The treatment can in the main be performed by immersing the tissue in various liquid agents. The present invention relates to a machine for successively performing these immersing functions.

The main object of the present invention is the provision of a new and improved automatic immersion apparatus for the treatment of histologic tissue prior to microscopic examination thereof.

Another object of the present invention is the provision of a new and improved means for moving tissue relative to a series of agent receptacles and for dipping said tissue in said receptacles in a prescribed sequence.

Still another object of the present invention is the provision of a new and simplified means for providing a step-by-step rotary movement to a multiplicity of circularly arranged receptacles, such movement being relative to a non-laterally movable tissue specimen.

Still another object of the present invention is the provision of a new and improved means for advancing in a step-by-step manner a circular row of receptacles a preselected angular distance in timed relation with the movement of a tissue specimen up and down, out of and into such receptacles.

Yet another object of the present invention is the provision of a new and improved means for holding a slide .on an automatic immersion apparatus.

Still another object of the present invention is the provision of a new and improved means for deenergizing an automatic immersion apparatus after it has completed its treatment cycle.

The above and other objects, characteristics and features of the present invention will be more fully understood from the following description taken in connection with the accompanying illustrative drawings.

In the drawings:

FIG. 1 is a perspective view of an automatic immersion apparatus embodying the present invention;

FIG. 2 is a top plan view of the apparatus of FIG. 1 with the receptacle support shown in phantom to enable other portions of the apparatus to be visible;

FIG. 3 is a bottom view of the apparatus illustrating the drive and timing mechanism therefor;

FIG. 4 is a vertical sectional view of the apparatus;

FIG. 5 is a vertical sectional view illustrating the means for moving the tissue specimen vertically into and out of an agent receptacle;

FIG. 6 is a circuit diagram of the electric circuits controlling the motor means for driving and timing the apparatus of FIG. 1;

FIG. 7 is a perspective view of a slide holder for bolding a plurality of tissue specimen slides for immersion into the plurality of receptacles by the present apparatus;

FIG. 8 is a rear elevational view of the slide holder of FIG. 7;

FIG. 9 is a bottom plan view of said slide holder;

FIG. 10 is a vertical sectional view of the slide holder 3,356,096 Patented Dec. 5, 1967 in cooperation with a special loading-unloading receptacle for slides; and

FIG. 11 is a top plan view of the special receptacle of FIG. 10.

Referring now to the drawings in detail, the automatic immersion apparatus embodying the present invention is generally designated by the reference numeral 10. Apparatus 10 includes a base 12 having a main support plate 16 here shown as square in configuration, and a peripheral side wall 14. Rotatably, mounted on the base 12 is a receptacle support 18 having a multiplicity of apertures 20 in which are disposed a corresponding multiplicity of receptacles 22. Means 30 are provided for pcriodically advancing the receptacle support 18 an angular distance equal to the the angular distance between two adjacent receptacles. Also mounted on the base 12 is a slide holder support 24 which supports one or more slide holders 26 that releasably hold a plurality of slides 28. The support 24 is mounted in the base 12 for vertical reciprocal movement, and means 29 are provided within the base 12 for moving the support 24 and hence the holder 26 and slides 28 up and down in timed relation ship with the movement of the receptacle support 18.

The means 30 for advancing the receptacle support 18 in a step-by-step motion is illustrated best in FIG. 4. Referring now to FIG. 4, it will be seen that the receptacle support 18 is detachably connected to the non-circular upper end 32 of a main vertical shaft 34 as by a complementary depending collar 35 which fits snugly around the non-circular upper end of the shaft and rotates therewith. For example, the shaft end 32 and the collar 35 can both be square or octagonal in cross-sectional shape. Thus, when it is desired to detach the receptacle support 18 from the shaft 34, all that has to be done is to lift the receptacle support off the shaft. It will be seen that when the receptacle support 18 is lowered about the shaft, the lower surface of the receptacle support engages a plurality, here shown as three in number, of wheels or roller bearings 37 to facilitate easy rotation of the receptacle support in the manner to be described hereinafter. The shaft 34 is rotatably mounted on the support plate 16 of base 12 as by washers 36 and 38.

Secured to the shaft 34 within base 12 as by a set screw 40 is a ratchet 42. As shown herein the ratchet 42 has a circular periphery and a multiplicity of depending studs or pins 44 which are engageable by a pawl 46 for relatively advancing the ratchet and hence the shaft 34. Naturally, if desired, the ratchet 42 could have a saw tooth peripheral configuration in the conventional manner. Pawl 46 is pivotally mounted on bracket 48 as by pivot pin 50 and is biased by coil spring 52 in a counterclockwise direction into engagement with the ratchet pins 44. Bracket 48 in turn is fixed to an arm 54 which is mounted on shaft 34 for limited longitudinal movement circumscribed by a slot 56. Biasing means here shown as tension spring 58 is provided to bias the arm 54 in what will hereinafter be called a retracted position. As shown, spring 58 is secured at one end to an end of the arm 54 and is secured at its other end to the base 12.

Means are provided for imparting longitudinal movement to the arm 54. whereby to cause the forward end of the pawl 46 to engage a ratchet pin 44 and advance the ratchet a predetermined distance equal to the angular distance between two adjacent receptacles on the receptacle support 18. This means includes a cam follower 60, here shown in the form of a rotatable wheel, mounted on the varm 54, and a cam 62 secured to the bottom surface of a main drive wheel 64 which drive wheel is rotatably mounted on shaft 34 for rotation independently of said shaft. Drive wheel 64 is a sprocket having a multiplicity of teeth engageable with a continuous drive chain 66 which extends around the wheel and around a drive sprocket 68 which in turn is driven through reduction gearing in a housing 70 by a motor 72. When the motor 72 is energized in a manner to be described hereinafter, it will drive the drive pinion 68 at a relatively low speed which speed will be further reduced by the chain 66 and the wheel 64 to impart a slOW angular movement to said wheel 64. The time of rotation of wheel 64 is equivalent to one complete immersion cycle in one receptacle including the displacement of slides 28 from that receptacle and into an adjacent receptacle. As the wheel 64 turns around, there will come a time when the leading edge 74 of the cam 62 engages the cam follower 60. As the wheel 64 continues rotating, the cam follower 60 will be displaced toward the left as viewed in FIG. 3 under the urging of the cam 62 and against the bias of the tension spring 58. This leftward motion of the arm 54 will impart a leftward motion to the pawl 46 which is in engagement with a specific ratchet tooth herein designated as 44a and will thrust the ratchet in a counterclockwise direction an angular distance determined by the displacement imparted by the cam 62. As the pawl pushes the ratchet 42 in a counterclockwise direction as viewed in FIG. 3, the shaft 34 will rotate therewith as the ratchet is secured to the shaft 34 as by the set screw 40. As the shaft 34 rotates it will impart a rotary movement to the receptacle holder 18 connected to the shaft and hence to the receptacles carried by the holder. This rotary movement will be facilitated by the rollers 37 on which the under surface of the receptable support 18 rides as previously described. After peak displacement of the arm 54 by the cam 62, the arm will be permitted to be restored to its initial position under the urging of the spring 58 against the receding trailing surface of the cam 62. This return movement of the arm 54 will not cause any return rotation of the ratchet 42 due to the fact that the pawl 46 moving in a rightward direction as viewed in FIG. 3 will ride over the pins 44 which riding will be permitted by the coil spring 52.

As previously noted, means 30 are provided for moving the tissue holder support 24 upwardly and downwardly in timed relation with the angular movement of the receptacle support 18. As may best be seen in FIG. 1, tissue holder support 24 is mounted for vertical reciprocal movement by guide pins 76 and 78 which are slidably received in sleeves 80 and 82 which are fixed to the main support plate 16 of the base 12. A drive pin 84 is fixed to the holder support 24 intermediate its two ends and extends into the base 12 in slidable relation with an encircling guide sleeve 86. The lower end of the rod 84 is pivotally mounted onto one end of a lever 90 as at 88. The lever 90 is pivotally mounted on a depending stud 94 as at 92 and is provided at its other end with a rotatable eccentric cam follower 98. The cam follower 98 is biased into engagement with the under surface of the drive sprocket 64 by any suitable biasing means, such as, for example, a tension spring 100 fixed at one end to the main support plate 16 and fixed at its other end to lever 90 between the cam follower 98 and pivot 92. Obviously, a spring acting in the opposite direction could be employed to provide the bias provided such a spring were connected on the other side of the lever pivot 92,

Depending from the under surface of the drive wheel 64 is a cam 102 having a leading edge 104 which starts out adjacent the wheel 64 substantially horizontal and gradually increases in steepness therefrom, a horizontal central portion 106 and a trailing portion 108 here shown to be a mirror image of the leading portion 104. As the main drive wheel 64 rotates, at some point in its travel the leading edge of the cam 102, namely edge 104, will engage the cam follower '98 and tend to move it downwardly away from the sprocket 64 and support plate 16. This downward movement of the cam follower 98 will be translated by the lever 92 into an upward movement of the pivot 88 and hence of the drive pin 84 whereby to move the holder support 24 upwardly, which movement will move the slide holder 26 upwardly and remove the slides 28 from the receptacle 22 in which they were immersed. As the drive sprocket 64 continues its rotational travel, the cam follower 98 will engage the horizontal portion 106 of cam 102 to hold the cam follower 98 in a fully depressed condition and therefore hold the support 24 in its fully raised position for a predetermined period of time depending upon the linear extent of the surface 106 and the rate of travel of the sprocket 64. As the cam continues to move past the cam follower 98, the cam follower will ultimately engage the trailing surface 108 of cam 102 and under the urging of the spring the cam follower will move back toward and finally into engagement with the under surface of the sprocket 64. This movement of the cam follower will be translated into a downward movement of the slide holder support 24 to cause the immersion of the slides 28 into a receptacle in register therewith.

In accordance with the invention and as best illustrated in FIG. 3, the cams 62 and 102 are angularly located relative to one another and in relation to their respective cam followers 60 and 98 so that the upward and downward movement of the slide holder support 24 is in a specific timed relation with the rotational movement of the receptacle support 18; namely an initial upward movement of the slide holder to remove the slides from a receptacle in which they were immersed, then a rotational movement of the receptacle support 18 to move the adjacent receptacle into register with the slides 28, and then a downward movement of the receptacle support 24 to move slide 28 downwardly into said next adjacent receptacle. Moreover, in accordance with the present invention the preferred placement of the two cams 62 and 102 is such that the rotational movement of the receptacle support 18 does not begin for a discrete time interval of the order of five seconds after the slides have been raised to their fully raised position. This so-called dwell period will enable a liquid agent clinging to the slides 28 to run off the slides and drip back into the receptacle from which the agent came in order to reduce contamination of the agent in the next adjacent receptacle when the next adjacent receptacle is moved into register with the slides and the slides are immersed therein. Thus, the engagement of the cam follower 60 by the cam 62 to effect the longitudinal reciprocal movement of arm 54 will preferably not take place until cam follower 98 has moved along the entire leading surface 104 of cam 102 and along a portion of the horizontal surface 106 of said cam 102. At that point in the travel of wheel 64, the cam 62 will come into cooperative engagement with the cam follower 60 to cause the operation of the pawl and ratchet previously described to effect a shifting of one receptacle 22 out of register with the raised slide holders and another receptacle 22 into such register.

In order to insure ideal registration between the slides 28 and a receptacle 22, and to prevent misalignment during immersion of the slides into a newly registered receptacle, an interfitting aligning means 110 is provided. This aligning means includes a pin 112 depending from the slide holder support 24 and a plurality of notches 114 in the periphery of the receptacle support 18, one notch for each receptacle. Assuming proper registration of a receptacle 22 with the slides 28, when the slide holder support 24 is lowered to immerse the slides into the registered receptacle, the pin 112 will fit into the notch 114 associated with the receptacle in register. However, if there is slight misalignment due to over travel by the pawl and ratchet drive previously described, this over travel, which inherently must be slight, will cause a slight misalignment between the pin 112 and the supposedly aligned notch 114. However, the pointed end 116 of the pin 112 will engage a wall of the notch 114 and as the lowering movement continues will cause a shift of the receptacle support 18 in order to accommodate the pin 112 and thereby give accurate registration.

-In accordance with another feature of the present invention, it should be noted that means previously described provide for a vibratory movement of the slides 28 when they are immersed in a receptacle 22. This increases the effectiveness of the agent action on the tissue specimens mounted on the slides 28. This desirable result stems from the rotatable mounting of the cam follower 98 on lever 98 eccentrically rather than concentrically of the cam followers central main axis. By mounting the followed 98 eccentrically, when the cam follower 98 is in engagement with the bottom surface of the wheel 64 with the wheel slowly rotating as previously described, the cam follower 98 will turn and thereby impart an oscillating movement to lever 90 which will be translated into a vertical simple harmonic movement in the drive post 84. This vibratory or limited simple harmonic movement of the drive post 84 will be imparted to the slide holder support 24 and hence to the slides 28, whereby to yield the desired result.

It is desirable to maintain the receptacles 22 covered except when they are actually in use. Such covering reduces contamination and evaporation. To substantially accomplish this end, a disc-like cover 118 of radius substantially equal to the receptacle support 18 is provided with the center thereof having a central aperture 120 adapted to receive an extension 123 on the upper end 32 of the shaft 34 with clearance for indexing the cover. The lower surface of the cover 118 rests on the tops of the receptacles 22 to cover them with the exception noted below. In the area of the slide holder support 24, the cover 118 is provided with a cut out 121 to expose those receptacles which are in use or about to be placed in use. Thus, the remaining receptacles are covered and the receptacles in the immediate zone of the slide holder support 24 are exposed for use. In order to maintain the cut out 121 in proper relation with the slide holder support 24, the cover 118 is further provided with a stop means in the form of an extension or protuberance 122 which is adapted to engage one of the guide posts 76 and thereby prevent rotation of the cover 118 with the receptacle support 18. Thus, during rotation of the receptacle support 18, the receptacles 22 will slide along the lower surface of the cover 118 which is prevented from moving therewith by the engagement of the protuberance 122 with the guide post 76.

As may best be seen in FIG. 1, a main power switch 124 is provided to control the supply of energy to the drive motor 72. An indicator lamp 126 is also mounted on the peripheral side Wall 14 of the base 12 for the purpose of indicating that the main power switch is in its on position. Also mounted on the side wall 14 is a second indicator lamp 128 which indicates when the machine has completed its cycle of operation. It will be obvious that once the machine has completed its cycle of operation it would be desirable for the machine to discontinue operation in order to prevent a recycling of the tissue specimens which would be extremely deleterious. To prevent the recycling of the machine after the complete treatment cycle of the tissue specimens and the slide 28, a limit switch 130 is mounted on the upper surface of the main support plate 16. The limit switch is provided with a normally closed contact 132 which controls the main energizing circuit for motor 72 and which opens upon completion of the cycle to condition the motor 72 for deenergization, and a normally open contact 134 which becomes closed upon a completion of the cycle in a manner to be described. Specifically, the receptacle support 18 is provided with a multiplicity of pin receiving apertures 136. Each of these apertures is adapted to receive a stop pin 138 which pin is readily removable therefrom and insertable in another of the apertures 136*. Thus, depending upon the cycle being employed in the apparatus 10, the machine can be caused to stop at any 6 preselected place depending upon the placement of the stop pin 138. When the stop pin moves into engagement with the switch 130' is causes the switch to operate from its normal condition to its operated condition wherein the contact 134 is closed and the contact 132 is open.

It will therefore be seen that as the receptacle support 18 is rotated for the final movement, the switch 130 will operate to open the main energizing circuit for motor 72. However, it has previously been noted that the rotational movement of the receptacle support 18 occurs only when the tissue holder support 24 is in its raised condition. If the machine 10 were deactuated with the tissue holder support 24 in its raised condition, then the slides 28 come to rest exposed to the air. This exposure to the air would be very deleterious to the slide specimens. In order to prevent the machine coming to rest in the raised condition a mercury switch 135 is mounted on the lever 90. The switch 135 is adapted to close and open a circuit depending upon the position of lever 90. The switch 135 is arranged so that it is opened when the lever is in its lowered condition and is closed at all other times. By utilizing the circuit elements above described in a circuit arrangement of the type illustrated in FIG. 6 the circuit elements can assure the deenergization of the motor 72 at the properly selected position and when and only when the slide holder support 24 is in its lowered position. This is accomplished in the following manner, referring to FIG. 6.

With the main switch 124 closed a circuit is established for energizing the power on lamp 126, which circuit may be traced from the positive terminal, through switch 124, and lamp 126 to the negative terminal. Motor 72 is also energized by the main energizing circuit which can be traced from the plus terminal, over closed switch 124, over closed contact 130132, and through the motor 72 to the negative terminal. This will cause the motor 72 to rotate and thereby slowly drive the sprocket 68 as a result of a reduction gearing in the chamber 70, to thereby even more slowly turn the main drive wheel 64 by means of the chain 66, to cycle the apparatus for rotational movement of the receptacle support 18 and its associated receptacles 22, and the up and down movement of slide holder support 24 and its associated slides 28 in the manner hereinbefore described. Each time the lever 90 is pivoted to raise the slide holder the mercury switch will operate, but this will have no effect on the apparatus as it merely closes and opens a second or parallel circuit for energizing the already energized motor 72. However, upon the completion of the next to last immersion of the slides in a receptacle, cam 102 will engage cam follower 96 and pivot the lever 90 to raise the slide holder support 24 to remove the slide 28 from the receptacle in which they were last immersed. This pivoting action will close the mercury switch 135. The closing of the switch 135 will have no immediate effect on the apparatus due to the fact that the motor 72 is energized by its previously traced main energizing circuit. However, when the cam 62 engages cam follower 60 to actuate the pawl and ratchet arrangement whereby to rotate the receptacle support 18, the pin 138 will move into operative engagement with switch 130 whereby to operate the switch from its normal condition to its operated condition in which the contact 132 is opened and the contact 134 is closed. This will establish an energizing circuit for the cycle complete lamp 128 which circuit may be traced from the positive terminal of the power source over the main switch 124, and over the contact 130-134 and through the lamp 128 to the negative terminal. In addition, the main energizing circuit for the motor 72 will be opened at the now open contact 132. However, this will not cause the deenergization of the motor 72 due to the auxiliary energizing circuit which may be traced from the positive terminal of the power source, over switch 124, through mercury switch 136 which is closed due to the lever 90 being out of its normal position, and through the motor 72 to the negative terminal. Thus, the motor 72 will continue to operate to rotate the wheel 64 until cam 62 moves out of engagement with cam follower 60 to cause a retraction of the pawl 46, and, more importantly, cam 102 moves out of engagement with cam follower 98 whereby to cause lever 90 to pivot back to its normal condition in which the slide holder support 24 is lowered and the slides 28 are immersed. At this point the mercury switch 135 will operate to its open condition whereby to open said auxiliary energizing circuit and deenergize the motor 72. The lamp 128 will remain energized as previously noted to indicate that the cycle has been completed and the lamp 126 will remain on to indicate that the main power switch 124 is in its closed condition.

It will be noted that with the simplified control and timing mechanism previously described, the slides 28 are immersed in each of the receptacles 22 for the same amount of time, namely the time it takes for the main sprocket to effect a complete revolution. There are often times where it is desirable to have the slides immersed in agents until specific results are obtained and then to remove the slides from those agents. Control of this can be effected in several ways. For example, control can be effected by a selection of the intensity of concentration of the respective agent solutions in the receptacles 22. That is to say, if a tissue specimen would be overexposed to a particular agent at full strength by keeping the specimen in the receptacle for the full period of immersion, often times this can be compensated for by reducing the concentration of the agent in the receptacle. Another means of controlling immersion time is to utilize the same agent in more than one receptacle. That is to say, if unduly long immersion times are required for a particular agent, two or possibly even three or more adjacent receptacles can be employed to contain the identical agent and thereby increase the immersion time for that agent.

The slide holder 26 is more particularly illustrated in FIGS. 7 through 10. Slide holder 26 has a main body portion 138 having a rear plate 140 with an outwardly extending upward shoulder 142. Body 138 also has a central web 144 which extends forwardly of the rear plate 140 to an angularly disposed front plate or surface 146. Extending forwardly of the front surface 146 in parallel spaced relation are a pair of cars 148 and 150. Extending along the bottom of the body 138 is a bottom plate or surface 152. The bottom surface 152, in combination with the front and back surfaces 146 and 140, respectively, and the web 144 define two finger gripping recesses 154 and 156.

Secured to the bottom 152 of main body portion 138 in depending relation therewith is a fixed jaw 158 having a substantially planar rear surface 160 and a saw toothed front surface 162 with a plurality of spaced apart slide receiving grooves 164. A pair of spaced apart circular channels 166 and 168 are provided in the fixed jaw 158 and in communication with the rear surface thereof, which channels provide a seat for screws 170 which secure the fixed jaw to the body 138 and which channels also provide an indexing means as will be more fully understood hereinafter. It will be noted that the front saw toothed surface 164 of fixed jaw 158 is preferably substantially in register with the bottom of front surface 146. A movable jaw 172 is provided for cooperation with the fixed jaw 158. The movable jaw 172 has a rear saw tooth surface 174 which confronts the saw tooth forward surface 162 of fixed jaw 158 and is provided with a plurality of spaced apart slide receiving grooves 176 which are in substantial alignment with the grooves 164 on the fixed jaw. Movable jaw 172 is secured to a Z-shaped bracket 178 as by screws 180 which Z-shaped bracket is pivotally mounted between the ears 148 and 150 of the body 138 as by pivot pin 182. The upper end of the Z-shaped bracket 178 extends upward to terminate substantially coplanarly with the upper surface of the body 138. This upper portion is designated by the reference numeral 184 and serves as a finger engaging extension and further provides a seat for a biasing compression spring 186. Specifically, the forward end of the spring 186 is seated in a depression 188 in the portion 184 of the Z-shaped bracket 178. The other end of the spring 186 is seated in a circular depression 190 in the surface 146 of the body 138. The compression spring 186 normally biases the Z- shaped bracket 178 to the position shown in FIG. 7, wherein the movable jaw 172 is in close spaced relation with the fixed jaw 158. However, when an operators finger is brought into engagement with bracket portion 184 and forces the bracket portion rearwardly toward surface 146 as illustrated in FIG. 10, the movable jaw 172 will pivot away from the fixed jaw 158. With the jaws so spread apart they are adapted to receive slides between them which slides will seat in the aligned grooves 164- 176 and be held between the jaws by the spring 186 when the portion 184 is released. Thus a plurality of parallel spaced vertically depending slides can be held by a single slide holder 26.

To improve the gripping or holding of slides, at least one of the jaws is preferably provided with a friction material such as rubber. As shown herein, movable jaw 172 is provided with a circular passage 173 which communicates with each of the grooves 176. Force fitted into passage 173 is a rubber tube 175 of slightly greater diameter. Thus a portion of tube 175 is disposed in the trough of each groove 176 for engagement with a slide 28 to securely hold the slide.

When the slide holder is so equipped with slides, it may be placed on the slide holder support 24 in the following manner. As may best be seen in FIG. 1, the upper edge of the slide holder support 24 is provided with a plurality of notches 192 which notches are adapted to provide a seat or indexing means for a slide holder 26. Provided on the slide holder is a pin 194 having an enlarged head 196 at the rear of the slide holder. The pin is biased forwardly of the slide holder by a tension spring having one end secured to the forward end of the pin 194 and its opposite end secured to a pin 200 which extends across the circular passage 202 in which the pin 194 is partially disposed. However, when it is desired to dispose a slide holder on the support 24, the operator grasps the pin head 196 and pulls the pin to the right as viewed in FIG. 10 whereby to enlarge the opening between the rear surface of the body 138 and the forward surface of the pin head in order to receive the slide holder support 24 therebetween. The slide holder is then moved down with the pin 194 be ing fitted into an appropriate notch 192 on support 24 whereupon the operator releases the pin head 196 and permits it to move to the left as viewed in FIG. 10 to press the slide holder support between the pin head and the rear surface of the body 138. To prevent any rocking movement, the horizontal protrusion 142 is provided which protrusion or shelf 142 rests on the upper surface of the slide holder support on both sides of the notch 192. Thus the slide holder is readily detachably mounted on the slide holder support and is accurately indexed thereon.

While the slides 28 can be manually loaded onto the slide holder 26 as previously described, this loading operation is somewhat d'ifiicult in that as one slide is being positioned a previously positioned slide can conceivably fall out. To overcome this possible difiiculty, a special loading and unloading receptacle 204 may be employed. Receptacle 204 is a substantially solid body having rectangular cavity 206 therein which cavity is adapted to receive a plurality of slides 29. Two opposed surfaces of the cavity 206, namely surfaces 208 and 210 are both saw toothed in configuration with slide receiving grooves 212 in each, which grooves are in alignment with the opposing slide receiving groove for ready slidable reception of a slide 28. With such a receptacle, the slides may be readily placed in the cavity 206 with their sides in the slide receiving grooves 212 whereby to arrange them in parallel spaced relation. The surfaces 208 and 210 are substantially identical to the jaw surfaces 174 and 162 on the holder 26 whereby to prearrange the slides in the relation required by the holder. Furthermore, the depth of the cavity 206 is such that a substantial portion of the slides 28 extend above the upper surface 214 of the receptacle 204 so that they may be grasped by the jaws of the slide holder 26.

When the slides 28 are arranged as shown in FIG. 11, then the slide holder 26 can be moved into appropriate relationship with the arranged slides and the movable jaw 172 then permitted to move into grasping relation with the slides 28 to trap them between the movable and fixed jaws for holding as previously described. To insure proper alignment of the slide receiving grooves 162 and 174 on the fixed and movable jaws 158 and 172, respectively, of the slide holder 26, a pair of indexing pins 216 and 218 are provided on theupper surface of the special receptacle 204, which pins are arranged to fit into the circular channels 166 and 168 in the rear surface of the fixed jaw 158 to thereby index the fixed jaw and the movable jaw with respect to the slides 28 in the cavity 206 of the receptacle 204. Thus a convenient means for loading and unloading the slide holder 26 is provided. If desired, cavity 206 of receptacle 204 may be filled with a neutral or treating agent as a preliminary and/or post treatment for the slides.

In use, one or more slide holders 26 will be loaded with one or a plurality of slides 28 by virtue of the load-- ing-unloading receptacle 204 and the movable and fixed jaws 172-158 of the slide holder 26, as previously described. The slide holder or slide holders will then be secured to the slide holder support 24 by disposing their respective indexing pins 194 in the preselected notch 192 on the upper surface of the slide holder support and with surfaces 142 resting on the upper edge of support 24. After the slide holders are so positioned, the main switch 124 is operated to its closed condition whereby to energize the main switch on light 126 and the motor 72 as previously described. The motor will commence operating and through the reduction gearing will drive sprocket 68 which, through the medium of chain 66, will continuously rotate wheel 64 on which the horizontal and vertical cams 62 and 102 are located. The sprocket wheel 64 will make a full revolution during which time the level 90 will oscillate by virtue of the eccentric action of cam follower 96 in engagement with the rotating sprocket 64 to thereby oscillate the slides. Near the completion of the full revolution the cam 102 Will engage the eccentric cam follower 96 and cause the lever 90 to pivot to raise the slide holder support 24 and to hold it in a raised position. After the slide holder support has been raised for a few seconds, a cam 62 will engage cam follower 60 to actuate the pawl and ratchet arrangement 4642, whereby to rotate the receptacle support 18 an angular distance equal to the spacing between adjacent receptacles 22. Upon the completion of the rotational movement of the receptacle support 18, cam 102 will move out from engagement with cam follower 98 to move the slide holder support 24 downwardly and again immerse the slides 28. This cycle will repeat through as many times as desired as determined by the placement of the stop pin 138. Upon the movement of the stop pin 138 into contact with switch 130, the main motor energizing circuit will be opened but the motor will continue to be energized until sprocket 64 has rotated sufliciently to permit the downward movement of slide holder support 24 whereupon mercury switch 135 will be opened to deenergize the motor 72 and stop op eration of the machine. The cycle complete light will have been turned on by the action of the pin 138 on the switch 130. Thus the machine will come to rest with the slides in their lowered or immersed position. When the operator next attends the machine he can remove the immersed slides together with their slide holder and reinsert the so held slides into the special container 204 and then release them from the slide holder by operation of movable jaw 172.

While we have herein shown and described the preferred form of the present invention and have suggested modifications therein, other changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of this invention.

What we claim is:

1. Automatic immersion apparatus for sequentially moving material into and out of a plurality of receptacles in a horizontal row, comprising means for supporting the plurality of receptacles in a horizontal row, means for supporting the material, means for raising and lowering said material support for moving material supported thereby out of and into a receptacle, means for moving said receptacle support horizontally for moving one of the receptacles in a row out of register with said material support and for moving another of the receptacles into register with said material support, and means for timing said last two mentioned means for operating said receptacle support moving means when said material support is in its raised position, said material support moving means, said receptacle support moving means and said timing means comprising a rotatable member having a pair of related mutually perpendicular cam surfaces thereon, one of said surfaces being included in each of said moving means.

2. The apparatus of claim 1, wherein said receptacle support moving means comprises a pawl and ratchet, and means for periodically operating said pawl in response to motion of its associated cam surface.

3. The apparatus of claim 1, wherein said material support moving means comprises a pivoted lever having a cam follower on one side of the pivot engageable with said rotatable member and the cam surface included in said material support moving means, and a vertically extending rod pivotally connected at one end to said lever on the other side of said pivot and connected at its other end to said material support.

4. The apparatus of claim 3, wherein said cam follower is rotatably eccentrically mounted on said lever.

5. The apparatus of claim 1, further comprising aligning means for positioning said receptacle support relative to said material support, said aligning means including a pair of interfitting means, one connected to said material holder and one connected to said receptacle support, said interfitting means being brought into and out of interfitting relation by the lowering and raising, respectively, of said material support.

6. The apparatus of claim 1, wherein said receptacle support means supports said receptacles in a circular horizontal row, and said means for moving said receptacle support is a means for rotating said receptacle support step-by-step about the axis of said circular horizontal row.

7. The apparatus of claim 6, further comprising a cover resting on the tops of a portion of said plurality of receptacles, said cover having a cut-out portion adjacent said material support for exposing at least one receptacle, and stop means for preventing said cover from moving with said receptacles.

8. The apparatus of claim 6, wherein said means for rotating said receptacle support comprises a ratchet, a rotatable shaft connected to the axis of rotation of said ratchet for rotation therewith and connected to the axis of rotation of said receptacle support for rotation therewith, a reciprocably movable pawl engageable with said ratchet to impart a step-by-step rotation thereto, and means for reciprocably moving said pawl including a rotatable wheel, a cam surface on said wheel, a cam follower operatively connected to said pawl, and means for biasing said cam follower into engagement with said cam surface.

9. The apparatus of claim 8, wherein said material support moving means comprises a second cam surface on said wheel, a pivoted lever, a second cam follower rotatably mounted on said lever, means for biasing said lever for positioning said second cam follower in the path of said cam surface, and means connecting said lever to said material support.

10. The apparatus of claim 9, wherein said cam follower is eccentrically mounted on said lever.

11. The apparatus of claim 9, wherein said timing means includes said wheel and the relative location of said cam surfaces on said wheel.

12. The apparatus of claim 11, wherein said second cam surface is positioned on said wheel relative to said first cam surface and shaped so that said material holder is held in its raised position for a predetermined time time interval prior to said first cam surface actuating said first cam follower to operate said pawl and ratchet.

13. The apparatus of claim 12, further comprising a motor for driving said rotatable wheel, a limit switch having a normal and an operated condition, means on said receptacle support for operating said limit switch upon said receptacle support being moved to a predetermined condition, a circuit for energizing said motor including said limit switch, said circuit being closed only when said switch is in said normal condition, a position sensitive switch fixed to said lever, said position sensitive switch being open when said material holder support is in its lowered position and being closed at other times, and a second energizing circuit for said motor including said position sensitive switch.

14. The apparatus of claim 13, further comprising means for enabling the selective positioning of said limit switch operating means on said receptacle support.

15. The apparatus of claim 9, further comprising a motor for driving said rotatable wheel, a limit switch having a normal and an operated condition, said receptacle support having a plurality of apertures, one for each receptacle, a pin removably disposable in said aperture, said pin being adapted to operate said limit switch when disposed in any of said apertures, and a circuit for energizing said motor including said limit switch, said circuit being closed only when said switch is in said normal condition.

16. The apparatus of claim 1, a material holder means for detachably connecting said material holder in said material support, said material holder including a pair of relatively movable jaws, and spring means for biasing said jaws toward one another for clampingly holding material therebetween.

17. The apparatus of claim 16, wherein said material support includes a band of rigid material extending in the direction of the path of movement of said receptacle support, said band having a notch in its upper edge, and said detachable connecting means comprising a vertically extending rear material holder wall, a horizontal shoulder extending rearwardly of said rear wall, a forwardly and rearwardly movable pin slidably mounted in said rear wall, stop means on said pin, means for biasing said pin forwardly into a position in which said stop means is spaced from said rear Wall a distance less than the thickness of said upper edge of said material support, said pin being disposed within said notch with said rear wall of said holder on one side of said support and stop means on the other whereby said pin biasing means forces said rear surface and stop means into clamping relation with said material support, said horizontal shoulder resting in engagement with said upper edge of said material support.

18. The apparatus of claim 17, wherein said jaws are provided in their mutually confronting surfaces with a plurality of spaced apart vertically grooves for receiving slides therein.

19. The apparatus of claim 16, wherein said jaws are provided in their mutually confronting surfaces with a plurality of spaced apart vertical grooves for receiving slides therein.

References Cited UNITED STATES PATENTS 2,496,506 2/1950 Wagner 134-58 2,645,236 7/1953 Fisher 134-61 2,646,807 7/1953 Martin 134-58 2,721,563 10/1955 Fisher 134-61 2,784,724 3/1957 Fisher 134-58 CHARLES A. WILLMUTH, Primary Examiner.

R. L. BLEUTGE, Assistant Examiner. 

1. AUTOMATIC IMMERSION APPARATUS FOR SEQUENTIALLY MOVING MATERIAL INTO AND OUT OF A PLURALITY OF RECEPTACLES IN A HORIZONTAL ROW, COMPRISING MEANS FOR SUPPORTING THE PLURALITY OF RECEPTACLES IN A HORIZONTAL ROW, MEANS FOR SUPPORTING THE MATERIAL, MEANS FOR RAISING AND LOWERING SAID MATERIAL SUPPORT FOR MOVING MATERIAL SUPPORTED THEREBY OUT OF AND INTO A RECEPTACLE, MEANS FOR MOVING SAID RECEPTACLES SUPPORT HORIZONTALLY FOR MOVING ONE OF THE RECEPTACLE IN A ROW OUT OF REGISTER WITH SAID MATERIAL SUPPORT AND FOR MOVING ANOTHER OF THE RECEPTACLES INTO REGISTER WITH SAID MATERIAL SUPPORT, AND MEANS FOR TIMING SAID LAST TWO MENTIONED MEANS FOR OPERATING SAID RECEPTACLE SUPPORT MOVING MEANS WHEN SAID MATERIAL SUPPORT IS IN ITS RAISED POSITION, SAID MATERIAL SUPPORT MOVING MEANS, SAID RECEPTACLE SUPPORT MOVING MEANS AND SAID TIMING MEANS COMPRISING A ROTATABLE MEMBER HAVING A PAIR OF RELATED MUTUALLY PERPENDICULAR CAM SURFACES THEREON, ONE OF SAID SURFACES BEING INCLUDED IN EACH OF SAID MOVING MEANS. 